Chemical sample, liquid

Chemical kit, 8, 9 Chemical sample, liquid, 6.1 Chemical sample, solid, 6.1 Chemical sample, toxic, liquid or solid, 6.1 First aid kit, 9 Gas identification set, 2.3 Gas sample, non-pressurised, n.o.s., not refrigerated liquid, 2.1, 2.3 Permeation devices, containing dangerous goods, for calibrating air quality monitoring Samples, explosive other than initiating explosives, 1... 

Figure 4. Photoacoustic signal measured in a sample liquid with an attached piezoelectric transducer having a resonant frequency of several tens of thousands of kilohertz. Note the change in scale of the amplitude and thus the much greater sensitivity of the detector at low light chopping frequencies. Argon ion laser light source, 400 mW, x = 488 nm sample 25 pg/mL BaSO powder suspended in aqueous glycerine. Reproduced with permission from Ref. 21 copyright 1980, American Chemical Society.

Loading and Compression Media. The loading procedures of the DAC depend on the thermodynamic properties and chemical characteristic of the sample. Liquid samples at ambient conditions are generally easy to be loaded, because a droplet can be positioned in the sample chamber to completely fill the gasket hole. Solid samples can be crumbled and cut in the desired dimensions and then positioned in the gasket hole. Powders as well can be loaded in the same way. 

Gas chromatography is a very unique and versatile technique. In its initial stages of development, it was applied to the analysis of gases and of vapors from very volatile components. The work of Martin and Synge (36) and then James and Martin (54) in gas-liquid chromatography (GLC) opened the door for an analytical technique which has revolutionized chemical separations and analyses. As an analytical tool GC can be used for the direct separation and analysis of gaseous samples, liquid solutions, and volatile solids. 

Comparative studies involving toxicity tests abound in the scientific literature. There are many reasons compelling ecotoxicologists to conduct work of this nature, some of which are directed 1) to assess the performance, sensitivity and relevance of individual bioassays undertaken on various chemicals and (liquid and solid) media to specify their scope of use, 2) to optimize the diagnostic potential of bioassay batteries to broaden hazard detection (insure that tests in a battery are complementary and not redundant) and 3) to promote the application of novel assays capable of high throughput for cost-effective screening of (complex) environmental samples. 

Initial screening of organic liquid samples focuses on the presence of volatile CWC-related chemicals. Organic liquid samples can be screened directly using techniques such as ... 

In contrast, when sampling bulk material, the material cannot generally be viewed as a set of distinct units. For example, we sample liquids from tanks, drums, and pipelines, and particulate solids such as ore, powders, and soil. Individual units cannot be identified for sampling. Rather, we must decide on a sample mass Mg or volume the chemical sample size. Further, we must be concerned about whether to composite samples, and, if so, how much to include in each increment of the composite. An additionaJ complication is the restriction on the sample mass that must be used in a chemical analysis due to the method or instrumentation. In fact, a subsample is usually taken in the lab. 

It s a far cry from the real thing, but a new artificial tongue promises to do a lot more than taste hamburgers and lick stamps. Chemist Eric Anslyn of the University of Texas at Austin and his coworkers have developed a prototype "tongue" biosensor for sampling liquids a tiny silicon wafer embedded with detection beads that turn color in the presence of specific chemicals. 

Related Terms Aerosols, see Aerosols, p.3 Ammunition, see Ammunition, p.8 Burster, see Ammunition, p.8 Cartridges, see Ammunition, p.8 Chemical sample, toxic, liquid or solid, see Chemical Kits and Samples, p.40 Expelling charge, see Ammunition, p.8 Flammable, see Flammable Solids and Division 4.1, p.99... 

The practical execution of viscosity measurements requires the use of good laboratory practice even if the experiments are relatively easy to do. Besides the basic safety regulations for the use of chemicals and liquids, a tidy sample preparation and a precise execution of the experiment is the prerequisite for the determination of the exact viscosimetry parameters of a polymer solution. 

Interference in electrothermal evaporation may stem from differences in the physical properties of the sample liquids from one sample to another. This may influence the wetting of the graphite or the metal of the electrothermal device. When the latter is temperature dependent, it leads to differences in volatilization. Differences in the anions present may severely influence evaporation (chemical matrix effect). The boiling points of the compounds formed dictate the volatilization. Accordingly. the occuiTence of double peaks is easily understood. In the case of Cd. this is documented for a sample rich in chloride (CdCh evaporates at... 

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